相关试题
【单选题】
开关接1时，电流表中流过的短路电流为___。
A. 0A
B. 0.2A
C. 10A
D. 约等于0.2A
【单选题】
正弦交流电常用的表达方法有___。
A. 解析式表示法
B. 波形图表示法
C. 相量表示法
D. 以上都是
【单选题】
电感两端的电压相位超前电流___。
A. 90°
B. 180°
C. 360°
D. 30°
【单选题】
电容两端的电压相位滞后电流___。
A. 30°
B. 90°
C. 180°
D. 360°
【单选题】
应用戴维南定理求含源二端网络的输入等效电阻是将网络内各电动势___
【单选题】
LC 选频振荡电路，当电路频率等于谐振频率时，电路性质为___。
A. 电阻性
B. 感性
C. 容性
D. 纯电容性
【单选题】
阻值为4Ω的电阻和容抗为3Ω的电容串联，总复数阻抗为___
A. 3+j4
B. 3-j4
C. 4+j3
D. 4-j3
【单选题】
电动势为10V，内阻为2Ω的电压源变换成电流源时，电流源的电流和内阻是___
A. 10A，2Ω
B. 20A，2Ω
C. 5A，2Ω
D. 2A，5Ω
【单选题】
电流为5A，内阻为2Ω的电流源变换成一个电压源时，电压源的电动势和内阻为___
A. 10V，2Ω
B. 2.5V，2Ω
C. 0.4V，2Ω
D. 4V，2Ω
【单选题】
额定电压都为220V的40W、60W、100W三灯泡串联在220V的电源中，它们的发热量由大到小排列为___
A. 100W 60W 40W
B. 40W 60W 100W
C. 100W 40W 60W
D. 60W 100W 40W
【单选题】
在正弦交流电的解析式i=ImSin(ωt +φ)中，φ表示___
A. 频率
B. 相位
C. 初相位
D. 相位差
【单选题】
正弦交流电压u=100Sin(628t + 600)V，它的最大值为___。
A. 100 V
B. 100 V
C. 60V
D. 628 V
【单选题】
能表示容性电路电压与电流关系的相量图是___。
【单选题】
电路中___定律指出：流入任意一节点的电流必定等于流出该节点的电流。
A. 欧姆
B. 基尔霍夫电流
C. 楞次
D. 基尔霍夫电压
【单选题】
已知电源电压为12 V ,四只相同灯泡的工作电压都是6 V，要使灯泡都能正常工作，则灯泡应___
A. 全部串联
B. 两只并联后与另两只串联
C. 两两串联后再并联
D. 全部并联
【单选题】
用戴维南定理分析电路“入端电阻”时，应将内部的电流源___处理。
【单选题】
任何一个含源二端网络都可以用一个适当的理想电压源与一电阻___来代替。
A. 串联
B. 并联
C. 串联或并联
D. 随意联接
【单选题】
用交流电流表测得交流电流10A，则电路中电流的最大值为___。
A. 10A
B. 14.1A
C. 20A
D. 70.7A
【单选题】
如右图所示电路中，已知各支路的电流I1=I2=10A， 则电路的总电流I为___。
A. 20A
B. 0 A
C. 14.1A
D. 50A
【单选题】
1杂质半导体中多数载流子的浓度取决于___
【单选题】
2在电场作用下，空穴与自由电子运动形成的电流方向___
【单选题】
4下列半导体材料哪一种的热敏性突出“导电性受温度影响最大”？___
A. 本征半导体
B. N型半导体质
C. P型半导体
【单选题】
5用万用表电阻挡检测某一个二极管时，发现其正、反电阻均近于1000KΩ，这说明该二极管是属于___。
A. 短路状态；
B. 完好状态；
C. 断路状态；
D. 极性搞错。
【单选题】
6稳压二极管是一个可逆击穿二极管，稳压时工作在___状态。
【单选题】
7三端集成稳压器CW7812的输出电压是___。
【单选题】
8三端集成稳压器CXX7805的输出电压是___
【单选题】
9一个平衡PN结，用导线将P区和N区连起来，而导线中___。
A. 有微弱电流
B. 无电流
C. 有瞬间微弱电流
【单选题】
10二极管两端正向电压大于___电压时，二极管才导通。
【单选题】
11当温度升高时，二极管的反向饱和电流 ___ 。
A. 增大；
B. 减小；
C. 不变；
D. 无法判定。
【单选题】
12硅二极管的正向导通压降比锗二极管的___ 。
【单选题】
13三端集成稳压器 CW7906的输出电压是___
【单选题】
14稳压管的工作是利用伏安特性中的___。
A. 正向特性
B. 反向特性
C. 反向击穿特性
【单选题】
15二极管具有___
A. 正向特性
B. 反向特性
C. 单向导电特性
D. 反向击穿特性
【单选题】
16图中D1-D3为理想二极管，A，B，C灯都相同，试问___灯最亮。
【单选题】
18在单相桥式整流电容滤波电路中，设U2为其输入电压，输出电压的平均值约为___。
A. U0=0.45U2
B. U0=1.2U2
C. U0=0.9U2
D. U0=1.4U2
【单选题】
19在单相桥式整流电路中，设U2为其输入电压，输出电压的平均值约为___。
A. U0=0.45U2
B. U0=1.2U2
C. U0=0.9U2
D. U0=1.4U2
【单选题】
20在半波整流电容滤波电路中，设U2为其输入电压，输出电压的平均值约为___。
A. U0=0.45U2
B. U0=1.2U2
C. U0=0.9U2
D. U0=1.4U2
【单选题】
21在半波整流电路中，设U2为其输入电压，输出电压的平均值约为___。
A. U0=0.45U2
B. U0=1.2U2
C. U0=0.9U2
D. U0=1.4U2
推荐试题
【单选题】
A virtual machine is connected on a distributed port group where the average bandwidth configured in the traffic shaping policy is 100 Mbps. The VM network adapter is configured with a reservation of 200 Mbps. What is the VM’s effective bandwidth?___
A. 200 Mbps
B. 100 Mbps
C. 150 Mbps
D. 400 Mbps
【多选题】
What are two reasons why a datastore in a Storage DRS cluster cannot enter maintenance mode?(Choose two.)___
A. Storage latency is too high to allow Storage DRS initiate Storage vMotion.
B. Storage DRS is configured for a VMFS3 datastore.
C. Storage
D. RS is disabled on the virtual disk.
【多选题】
What two methods are used to configure VMware vSphere Storage I/O Control shares and limits? (Choose two.)___
A. Assign shares and limits to VM virtual disks.
B. Assign shares and limits to datastores.
C. Assign shares and limits to Storage (DRS) clusters.
D. Assign shares and limits using VM storage policies.
【多选题】
ESXi 6.5 introduces VMFS6, which supports both 512e and 512n devices. What three configurations are supported when using these devices? (Choose three.) ___
A. Hosts with both 512e and 512n devices.
B. Storage vMotion between both 512e and 512n devices.
C. Datastore Extents spanned between both 512e and 512n devices.
D. Storage DRS clusters containing only both 512e and 512n devices.
【多选题】
A vSphere Administrator observes that the Primary VM configured with Fault Tolerance is executing slowly. After further investigation, it is determined that the Secondary VM is on an overcommitted ESXi host. What two methods will correct the problem? (Choose two.)___
A. Use Storage vMotion to migrate the Secondary VM to another datastore.
B. Use vMotion to migrate the Secondary VM to a different ESXi host.
C. Configure a CPU limit on the Primary VM which will also apply to the Secondary VM.
D. Turn off and turn on FT in order to recreate the Secondary VM on a different datastore.
【多选题】
Which two features require the use of Host Profiles? (Choose two.)___
A. Host Customizations
B. shared storage
C. Auto
D. eploy
【多选题】
What three processes on the vCenter Server Appliance (VCSA) does“vmware-watchdog monitor? (Choose three.) ___
A. vmware-eam
B. vmcad
C. vmware-vpostgres
D. vpxd
E. vsan-health
【多选题】
What three processes on the vCenter Server Appliance (VCSA) does“vmware-watchdog monitor? (Choose three.) ___
A. vmware-eam
B. vmcad
C. vmware-vpostgres
D. vpxd
E. vsan-health
【多选题】
Which two statements correctly describe VM-Host affinity rules? (Choose two.) ___
A. When there is more than one VM-Host affinity rule in a vSphere DRS cluster, the rules are applied equally.
B. After creating a VM-Host affinity rule, its ability to function in relation to other rules is predetermined.
C. When there is more than one VM-Host affinity rule in a vSphere
D. RS cluster, the rules will be ranked.
【多选题】
An administrator wants to enable proactive HA by moving virtual machines automatically if a hardware alert is triggered. What are the three required settings? (Choose three.)___
A. Set vSphere DRS Automation to Partially Automated.
B. Turn on Proactive HA.
C. Set the Proactive HA Automation Level to Manual.
D. Set the Proactive HA Automation Level to Automated.
E. Turn on vSphere HA and vSphere DRS.
【多选题】
If vCenter Server 5.5 installation has one or more services deployed remotely, which three services are relocated to vCenter Server 6.5 on upgrade? (Choose three.)___
A. vCenter Inventory Services
B. vSphere Authentication Proxy
C. vSphere Web Client
D. vSphere
E. SXi Dump Collector
【多选题】
What two debugging levels can a virtual machine be configured to? (Choose two.)___
A. Verbose
B. Debugging
C. Statistics
D. Trivia
【多选题】
What are three benefits of using a few large-capacity LUNs instead of many small-capacity LUNs? (Choose three.) ___
A. Better performance because there is less contention for a single volume.
B. More flexibility for resizing virtual disks.
C. Less wasted storage space.
D. More flexibility to create virtual machines without adding new LUNs.
E. Fewer VMFS datastores to manage.
【多选题】
Which two configurable options are available in Boot Options for a virtual machine? (Choose two.)___
A. Tools Upgrades
B. Encryption
C. Firmware
D. Force BIOS setup
【多选题】
Which three VMware-recommended best practices should an administrator follow before upgrading to vSphere 6.5? (Choose three.)___
A. Disconnect ESXi host from vCenter.
B. VMware Tools are installed in the virtual machine.
C. Ensure that the system hardware complies with ESXi requirements.
D. Back up the host.
E. Check the interoperability of any other software integrated with vSphere.
【多选题】
What are two requirements to enable EVC in vSphere DRS cluster? (Choose two.)___
A. CPUs must be from the same vendor.
B. EVC must use the lowest possible baseline supported by the hardware.
C. CPUs must be in the same family and of the same speed.
D. No VMs may be running in the cluster.
【多选题】
What three conditions could result in VMware Flash Read Cache being unable to claim a disk? (Choose three.)___
A. The disk is not listed in the VMware hardware compatibility guide.
B. The disk is not detected as an SSD.
C. The disk is not detected as local.
D. The disk is in use by VMFs.
【多选题】
Boot from SAN is supported on which three storage technologies? (Choose three.)___
A. VMware vSAN
B. FCoE
C. NFS 4.1
D. iSCSI
E. FC
【多选题】
Which two components are part of storage I/O multipathing on ESXi? (Choose two.)___
A. SATP
B. VASA
C. PSP
D. VAAI
【多选题】
Which two statements are true about Highly Available vSphere Auto Deploy infrastructure? (Choose two.)___
A. It helps prevent data loss.
B. It is a prerequisite for using vSphere Auto Deploy with stateful install.
C. It requires two or more Auto
D. eploy servers.
【多选题】
The virtual machine log rotation size can be changed for all VMs by which two interfaces? (Choose two.)___
A. PowerCLI
B. vSphere Web Client
C. ESXi host client
D. esxcli
【多选题】
Which two configuration options can exclude virtual disks from snapshot operations? (Choose two.)___
A. Use RDM in virtual mode for virtual disk.
B. Use virtual disks in Independent – Persistent mode.
C. Use a virtual disk larger than 2 TB in size.
D. Use RDM in physical mode for virtual disk.
【多选题】
Which two storage configurations on the source server are unsupported with VMware Converter? (Choose two.)___
A. Linux LVM
B. software RAID
C. GPT/MBR hybrid disks
D. Windows basic volumes
E. Windows dynamic volumes
【多选题】
Which two statements about vCenter HA are correct? (Choose two.)___
A. ESXi 5.5 or later is required.
B. vCenter HA network latency between nodes must be less than 50 ms.
C. NFS datastore is supported.
D. It must be deployed on a 3
E. SXi host cluster with DRS enabled.
【多选题】
An attempt to delete NFS datastore from a ESXi host returns the error: Sysinfo error on operation returned the following status:< Busy> Which two statements could explain this failure? (Choose two.)___
A. NFS datastore is a part of Storage DRS Cluster.
B. NFS.VolumeRemountFrequency value is set to 30.
C. Storage I/O Control is enabled on NFS datastore.
D. NFS datastore has running or registered virtual machines.
【多选题】
An administrator finds that the Microsoft Exchange virtual machines are exhibiting network latency. What two in-guest changes can help decrease latency? (Choose two.)___
A. LRO
B. TSO
C. SR-IOV
D. PVRDMA
【多选题】
Which two types of iSCSI adapters require VMkernel networking configuration? (Choose two.)___
A. dependent hardware
B. in-guest
C. software
D. independent hardware
【多选题】
Which two statements are true for NFS v4.1 firewall behavior? (Choose two.)___
A. It closes port 2049.
B. It sets allowed. All flag to TRUE.
C. It sets allowed. All flag to FALSE.
D. It opens port 2049.
【多选题】
A vSphere Administrator attempts to enable Fault Tolerance for a virtual machine but receives the following error: Secondary VM could not be powered on as there are no compatible hosts that can accommodate it. What two options could cause this error? (Choose two.)___
A. The other ESXi host(s) are in Maintenance Mode.
B. Hardware virtualization is not enabled on the other ESXi host(s).
C. The other ESXi host(s) are in Quarantine Mode.
D. Hardware MMU is enabled on the other
E. SXi host(s).
【多选题】
Storage capabilities be populated in what two ways? (Choose two.)___
A. The administrator can use tags to describe capabilities.
B. Default capabilities are provided by vCenter Server.
C. Datastores can advertise their capabilities through VAAI.
D. Datastores can advertise their capabilities through VASA.
【多选题】
In network troubleshooting it is important to know what upstream switch the ESXi host is connected to. Which two features does ESXi provide to help identify the upstream switch? (Choose two.)___
A. Promiscuous mode
B. DPM
C. LLDP
D. CDP
【多选题】
Virtual Volumes supports which three VMware features? (Choose three.)___
A. Instant Clones
B. Distributed Resource Scheduler
C. Linked Clones
D. vMotion
E. Storage Distributed Resource Scheduler
【多选题】
vSphere DRS helps to balance virtual machines with available resources in a vSphere cluster. What three types of resources can be taken into account for balancing? (Choose three.)___
A. CPU
B. physical NIC saturation of an ESXi host
C. virtual NIC saturation of a virtual machine
D. RAM
E. storage latency
【多选题】
Which three design requirements must be satisfied to enable RAID-6 objects in a VMware vSAN cluster? (Choose three.)___
A. vSAN Advanced license or higher
B. vSAN stretched cluster
C. at least six hosts contributing storage
D. deduplication and compression
E. all flash configuration
【多选题】
When using "Cluster resource percentage" for host failover capacity in vSphere HA Admission Control, the total resource requirements are calculated from which two values? (Choose two.)___
A. Total vCPUs assigned to each VM.
B. Average CPU usage on each VM over time.
C. Memory reservations on each VM.
D. Total memory assigned to each VM.
E. Average active memory on each VM over time.
F. CPU reservations on each VM.
【多选题】
Which are four attributes of the Active vCenter HA node? (Choose four)___
A. It uses the vCenter HA network to communicate with the Witness node.
B. It constantly replicates vPostgres data with the Witness node.
C. It uses a public IP address for the management interface.
D. It runs the active vCenter Server Appliance instance.
E. It uses the vCenter HA network for replication of data to the Passive node.
F. It provides a quorum to protect against split-brain situations.
【多选题】
Which are two vCenter Server two-factor authentication methods? (Choose two.)___
A. RSA SecurID
B. Smart Card
C. SAML
D. Symantec VIP
【多选题】
An administrator is creating VMkernel adapters on an ESXi 6.5 host and wants to create separate VMkernel adapters for every type of traffic in the default TCP/IP stack. Which three types of traffic can be explicitly enabled on a separate VMkernel adapter? (Choose three.)___
A. Virtual SAN traffic
B. NFS traffic
C. vMotion traffic
D. vSphere HA traffic
E. Fault Tolerance logging traffic
【多选题】
When migrating a Windows vCenter Server 6.0 to the vCenter Server Appliance 6.5, which two will be migrated by default? (Choose two.)___
A. Local Windows OS users and groups
B. Configuration
C. Custom ports
D. FQDN
E. Historical and Performance data
【多选题】
Which three types of Content Libraries exist within vSphere 6.5? (Choose three.)___
A. Remote Content Library
B. Published Content Library
C. Local Content Library
D. Shared Content Library
E. Subscribed Content Library
